Sphegina (Asiosphegina) cultrigera, Hippa, Heikki, Steenis, Jeroen Van & Mutin, Valeri A., 2015

Hippa, Heikki, Steenis, Jeroen Van & Mutin, Valeri A., 2015, The genus Sphegina Meigen (Diptera, Syrphidae) in a biodiversity hotspot: the thirty-six sympatric species in Kambaiti, Myanmar, Zootaxa 3954 (1), pp. 1-67 : 45-46

Sphegina (Asiosphegina) cultrigera sp. n.

Figs 27 A–D

MALE. Body length 5.3 mm, wing length 4.5 mm. Head. Face weakly concave and weakly projected anteroventrally; frontal prominence very weakly developed (similar to Fig. 1E). Width of vertex at anterior ocellus:width of head 1:4.1; depth of occipital concavity ca. 1/10 of the width of an eye in dorsal view. Width of face:width of head 1:5.0. Face black, pale pollinose. Gena shiny black. Frons and vertex semi-shiny black, lunula brownish, posterior to lunula with indistinct pale pollinosity, the pile short, infrequent, erect and pale. Occiput dull black. Eyes along face with area of enlarged facets. Antenna brown; basoflagellomere oval, baso-ventrally reddish, ratio of length:width 1:0.8; arista almost bare. Thorax. Colour black, mostly pale pollinose, all the pile very short, infrequent, adpressed and pale; scutellum trapezoidal, shiny dorsally, with a pair of pale, thin, well separated setae at apical margin. Wing. Hyaline, stigma brownish. Legs. Pro- and mesoleg yellow, tarsomeres 4 and 5 black. Metaleg: coxa brown; trochanter simple, yellow; femur yellow, the apical 1/6 and a broad annulus on the basal 1/2 brown; tibia without apico-ventral tooth, yellow except the apical 1/4 black and brownish annulus on the basal 1/2 medially; tarsus dark brown. Abdomen. Length ratio of tergites I, II, III and IV 1:2.7:1.5:1.1. Tergites shiny black, tergite III with a yellow subanterior fascia, nearly 1/2 as wide as the length of tergite; the pile of tergites pale, very short, adpressed, becoming longer towards the lateral margin; tergite I with an oblique row of 4 pale setae laterally; sternite IV ( Figs 27 A, D) brown anteriorly and brownish posteriorly, with short pale pile, the sword-like lobe on the left side pale yellowish; sternite VI ( Figs 33 A, D) with a very small tubercle at the posterior margin, black, the pile dense, pale, adpressed; sternites VII and VIII black, the pile short and pale. Genitalia, Figs 27 B, C. Note the slightly asymmetrical surstyli and the enlarged cercus. The superior lobes are symmetrical. FEMALE. Unknown.

Type material. HOLOTYPE. ♂, N.E. Burma, Kambaiti, 2000 m, 18.v.1934, R. Malaise ( SMNH). PARATYPE. 1♂ with same data as holotype except 7000 ft., 12. v. and Sphegina lateralis Dsbg det. v. Doesburg ( NBC).

Etymology. The name is from Latin, cultrigera , bearing a knife, referring to the knife-like lobe on the male sternite IV.

Discussion. Sphegina cultrigera is similar to S. siculifera , S. ensifera , and S. philippina Thompson, 1999b . These species differ from all other Sphegina by having a long sword-like lobe postero-laterally on the left side of the male sternite IV. The distinguishing characters between the first three species are discussed under S. siculifera below. S. philippina differs distinctly from all other species similar to S. cultrigera by male genitalia with small cerci and strongly asymmetric surstyli as well as by having its metatibia produced into a spur apicoventrally and the metafemur lacking a subapical paler annulus.

cultrigera ensifera siculifera sinesmila minuta parvula pusilla Colour of gena black brown brown brown light-brown light-brown brown

Figures

FIGURE 27. Sphegina (Asiosphegina) cultrigera sp. n. (holotype). A. Posterior part of abdomen, lateral view. B. Genitalia, lateral view. C. Left surstylus, lateral view. D. Posterior part of abdomen, ventral view. Scale 0.5 mm.

FIGURE 33. Sphegina (Asiosphegina) pusilla sp. n. (holotype). A. Posterior part of sternite IV, ventral view. B. Genitalia, lateral view. C. Right surstylus, lateral view. D. Left surstylus, lateral view. Scale 0.5 mm.